KR102057211B1 - Electrochemical ammonia gas sensor - Google Patents

Abstract

The present invention relates to an electrochemical ammonia gas sensor. According to an embodiment of the present invention, the electrochemical ammonia gas sensor includes: a housing including a gas inlet formed in the upper part to receive gas from the outside and a storage part formed in the lower part of the gas inlet; a sensing electrode placed under the gas inlet in the housing, including a catalyst for a chemical reaction to ammonia, and creating a hydrogen ion (H+) by decomposing the ammonia by making a chemical reaction to ammonia gas flowing in through the gas inlet; a reference electrode placed under the sensing electrode in the housing; a counter electrode placed under the reference electrode in the housing, and creating water from hydrogen ions through a reduction reaction; a separator structure carrying an ionic liquid electrolyte supplying hydrogen ions to at least one among an oxidation reaction occurring in the sensing electrode and a reduction reaction occurring in the counter electrode, and including a first separator placed between the sensing electrode and the reference electrode, a second separator placed between the reference electrode and the counter electrode and a third separator placed under the counter electrode; and an electrolyte carrier placed under the third separator in the housing, and carrying an excessive amount of ionic liquid electrolyte so as to supply the ionic liquid electrolyte to the separator structure.

Description

Electrochemical Ammonia Gas Sensor {ELECTROCHEMICAL AMMONIA GAS SENSOR}

The present invention relates to an electrochemical gas sensor, and more particularly to an electrochemical ammonia gas sensor.

Amperometric electrochemical gas sensors have been widely used in industrial safety equipment and process control applications. The electrostatic potential electrochemical gas sensor is based on the principle of a fuel cell, and the gas introduced into the sensor through the gas inlet passes through the gas permeable membrane and undergoes oxidation and reduction reactions at the electrode. This electrical signal is used to measure the concentration of gas.

The electrostatic gas electrochemical gas sensor is more linear and repeatable than the contact combustion gas sensor, colorimetric gas sensor, or semiconductor gas sensor, and can be quantitatively measured, and its manufacturing cost is lower than that of the optical gas sensor. It is used as a key component for gas measurement.

Most commercially available electrostatic potential ammonia gas sensors have ammonia gas diffused from the outside into the sensor without direct oxidation reaction at the electrode, and ammonium ion (NH4) through water in the electrolyte as shown in Equation (1) below. It is converted to ^{a) +)} and hydroxide ions (OH. And the oxidation reaction, such as the manganese-containing ion in the electrolyte (Mn ^{+ 2)} to the oxidized Formula (2) is to occur, it indicates a current output that is proportional to the concentration of ammonia gas.

NH ₃ + H ₂ O → NH ₄ ⁺ + OH ^- Formula (1)

Mn ^{2 +} + 2H ₂ O → MnO ₂ + 4H ⁺ + 2e ^- formula (2)

In the conventional electrochemical ammonia gas sensor, manganese dioxide (MnO ₂ ) generated during the oxidation reaction is precipitated into the electrolyte, and there is a problem in that long-term stability is lowered by blocking electrodes or gas inlets, and ammonia gas is dissolved in the electrolyte. Since an oxidation reaction occurs, the reaction time is relatively slow.

In addition, since the electrolyte used in the conventional electrochemical ammonia gas sensor uses an alkali-based aqueous solution such as lithium chloride (LiCl), the electrolyte is easily evaporated in a high temperature and low humidity environment and has a short lifespan of less than 1 year.

In addition, since the conventional electrochemical ammonia gas sensor reacts to an interference gas such as hydrogen sulfide (H ₂ S) and nitrogen monoxide (NO) in a considerable amount, the accuracy of ammonia gas concentration measurement is inferior.

The present invention has been proposed to solve the conventional problems such as the influence of the interference gas and the reaction time delay as described above, by using an ion-transport liquid electrolyte and an electrode containing a catalyst for the oxidation reaction of ammonia gas, An object of the present invention is to provide an electrochemical ammonia gas sensor capable of inducing an oxidation reaction of ammonia gas directly at an electrode to shorten the reaction time and minimize the influence of an interference gas.

In order to solve the above technical problem, an embodiment of the electrochemical ammonia gas sensor according to the present invention is a gas inlet through which an external gas flows is formed in the upper portion, the housing is formed in the lower portion of the gas inlet; The housing is disposed below the gas inlet, and includes a catalyst for the oxidation reaction of ammonia. The ammonia gas in the gas introduced through the gas inlet is oxidized to decompose ammonia to generate hydrogen ions (H ⁺ ). Sensing Electrode (Sensing Electrode); A reference electrode disposed below the working electrode in the housing; A counter electrode disposed below the reference electrode in the housing and generating water from hydrogen ions through a reduction reaction; A first separator supporting an ionic liquid electrolyte for supplying hydrogen ions to at least one of an oxidation reaction occurring at the working electrode and a reduction reaction occurring at the corresponding electrode, wherein the first separator is disposed between the working electrode and the reference electrode; A separator structure including a second separator disposed between a reference electrode and the counter electrode, and a third separator disposed below the counter electrode; And an electrolyte carrier disposed under the third separator in the housing and supporting an excess of the ionic liquid electrolyte to supply the ionic liquid electrolyte to the separator structure.

In some embodiments of the electrochemical ammonia gas sensor according to the present invention, the catalyst included in the working electrode may be ruthenium (Ru) nanoparticles.

In some embodiments of the electrochemical ammonia gas sensor according to the present invention, the diameter of the ruthenium nanoparticles may be 1 to 10 nm.

In some embodiments of the electrochemical ammonia gas sensor according to the invention, the ionic liquid electrolyte is 1-butyl-1-methylpyrrolinium bis (trifluoromethylsulfonyl) imide, 1-buthyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, 1 -Ethyl-3-methylmidazolium Acetate, 1-Ethyl-3-methylimidazolium bis (trifluoromethylsulfornyl) imide, 1-Ethyl-3-methylimidazolium dicyanamide, 1-Ethyl-3-methylmidazolium methanesulfonate, 1-Ethyl-3-methylimidazolium tetrafluoromethanesulfonate, 1- It may include one or more selected from methyllimidazolium chloride, 1-Methylimidazolium hydrogen sulfate, propylene carbonate, Methyl-trioctylammonium bis (trifluoromethylsulfonyl) imide, and Triethylsulfonium bis (trifluoromethylsulfonyl) imide.

In some embodiments of the electrochemical ammonia gas sensor according to the present invention, the ionic liquid electrolyte may include 1-Ethyl-3-methylmidazolium Acetate.

In some embodiments of the electrochemical ammonia gas sensor according to the invention, the ionic liquid electrolyte may further comprise one or more additives selected from KCl, LiBr, LiCl and NaCl.

In some embodiments of the electrochemical ammonia gas sensor according to the present invention, the additive may be contained in the ionic liquid electrolyte 2 to 5% by weight.

The electrochemical ammonia gas sensor according to the present invention performs oxidation and reduction reaction of ammonia gas by adjusting the conditions suitable for the oxidation potential energy of ammonia gas through proper mixing of the catalyst and ionic liquid electrolyte for the ammonia oxidation reaction included in the working electrode. There is an effect that facilitates and maintains a stable sensor signal. Accordingly, the electrochemical ammonia gas sensor according to the present invention can minimize the interference caused by an interference gas such as hydrogen sulfide (H ₂ S) gas and nitrogen monoxide (NO) gas.

In addition, the electrochemical ammonia gas sensor according to the present invention is a method of inducing oxidation of ammonia gas directly at the electrode, rather than measuring the pH of the electrolyte in which ammonia gas is dissolved into a conventional electrolyte. It has the effect of shortening the reaction time.

In addition, since the electrochemical ammonia gas sensor according to the present invention uses an ionic liquid electrolyte, the low vapor pressure characteristic of the ionic liquid electrolyte minimizes the evaporation of the electrolyte in the sensor, thereby increasing the life of the sensor.

1 is a schematic cross-sectional view of an embodiment of an electrochemical ammonia gas sensor according to the present invention.
2 is a view showing a current output value of the electrochemical ammonia gas sensor according to the present invention reacts to six kinds of gases including ammonia gas.
3 is a diagram showing an output ratio (%) of the ammonia gas output value for the six types of gas including the ammonia gas in the electrochemical ammonia gas sensor according to the present invention.
4 is a view showing a reaction time (T ₉₀ ) of the electrochemical ammonia gas sensor according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art, and the following examples can be modified in various other forms, and the scope of the present invention is It is not limited to an Example. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the inventive concept to those skilled in the art.

In the figures, for example, variations in the shape shown may be expected, depending on manufacturing techniques and / or tolerances. Thus, embodiments of the present invention should not be construed as limited to the specific shapes of the regions shown herein, but should include, for example, changes in shape resulting from manufacturing. Like numbers refer to like elements all the time. Furthermore, various elements and regions in the drawings are schematically drawn. Accordingly, the invention is not limited by the relative size or spacing drawn in the accompanying drawings.

1 is a schematic cross-sectional view of an embodiment of an electrochemical ammonia gas sensor according to the present invention.

Referring to FIG. 1, the electrochemical ammonia gas sensor 100 according to an embodiment of the present invention includes a housing 10A and 10B, a dust filter 11, a working electrode 32A, and a reference electrode. Electrode 32B, Counter Electrode 32C, Porous Membrane Structures 31A, 31B, 31C, Membrane Structures 33A, 33B, 33C, Electrolyte Carrier 40, Current Collectors 21A, 21B , 21C) and sensor pins 20A, 20B, 20C.

The housings 10A and 10B are composed of a lower housing 10B and an upper housing 10A having an accommodating portion therein, and the lower housing 10B and the upper housing 10A can be separated and combined. 1 is a schematic cross-sectional view of the electrochemical ammonia gas sensor 100 according to the present embodiment for the purpose of understanding the present embodiment, and the lower housing 10B and the upper housing 10A are ultrasonic. The inner parts of the electrochemical ammonia gas sensor 100 according to the present embodiment are hermetically sealed by fusion, and are disposed in a space formed by combining the lower housing 10B and the upper housing 10A.

In the central portion of the upper housing 10A, a gas inlet 12 through which gas is introduced into the housings 10A and 10B is formed, and ammonia gas is also introduced into the housings 10A and 10B through the gas inlet 12. The amount of gas introduced and introduced into the housings 10A and 10B is controlled through the gas inlet 12. The upper housing 10A may be made of ABS (acrylonitrile butadiene styrene copolymer), PE (polyethylene), PP (polypropylene), and the like, and the upper housing 10A has a diameter of 17 to 18.5 mm and a thickness of 2 to 4 It may be formed in a size of about mm. The diameter of the gas inlet 12 may be formed to a size of about 3 to 6 mm.

The lower housing 10B is formed in a cylindrical structure in which an accommodating part is formed to stack internal parts, and sensor pins 20A, 20B, and 20C are formed at a lower end of the lower housing 10B. The lower housing 10B may be made of ABS (acrylonitrile butadiene styrene copolymer), PE (polyethylene), PP (polypropylene), and the like, and the lower housing 10B may have a diameter of 20 mm and a height of about 16.5 mm. Can be formed.

The sensor pins 20A, 20B, and 20C formed at the bottom of the lower housing 10B are electrically connected to the current collectors 21A, 21B, and 21C. More specifically, the working electrode current collector 21A is physically connected to the working electrode 32A and the working electrode sensor pin 20A to receive an electrical signal generated by the oxidation reaction of the working electrode 32A. 20A). The reference electrode current collector 21B is physically connected to the reference electrode 32B and the reference electrode sensor pin 20B to transmit an electrical signal that is maintained at the electrostatic potential without participating in oxidation and reduction reactions to the reference electrode sensor pin 20B. do. The counter electrode current collector 21C is physically connected to the counter electrode 32C and the counter electrode sensor pin 20C to transfer an electrical signal generated by the reduction reaction of the counter electrode 32C to the counter electrode sensor pin 20C. do. The current collectors 21A, 21B, and 21C which are in direct contact with the ionic liquid electrolyte in the sensor 100 may be made of precious metals such as tantalum (Ta) or platinum (Pt) having excellent chemical resistance. The thickness may be in the form of a wire or ribbon within 0.15 mm.

The working electrode sensor pin 20A, the reference electrode sensor pin 20B, and the corresponding electrode sensor pin 20C are protruded to enable physical connection with the socket portion of the external electronic device, and the working electrode sensor pin 20A is operated. The electrical signal of the electrode current collector 21A is transmitted to the external device, the reference electrode sensor pin 20B transmits the electrical signal of the reference electrode current collector 21B to the external device, and the corresponding electrode sensor pin 20C is corresponding. The electrical signal of the electrode current collector 21C is transmitted to an external device. These sensor pins (20A, 20B, 20C) is in the form of a brass material, the surface is used to plate gold (Au), the sensor pins (20A, 20B, 30C) is 9 mm in length, 1.5 mm in diameter It can be formed to a degree.

The dust filter 11 is disposed to cover the gas inlet 12 at the upper end of the upper housing 10A to prevent liquids such as dust and moisture from being introduced into the housings 10A and 10B from outside and become contaminated. The dust filter 11 may be made of porous PTFE (polytetrafluoroethylene) material having a thickness of about 0.2 mm having chemical resistance. The fine pores of the dust filter 11 may have a size of about 0.2 to 0.5 μm, and a mesh-like structure made of plastic such as polyethylene (PE) may be adhered to the surface in order to increase mechanical strength.

The first porous membrane 31A and the working electrode 32A are sequentially disposed below the upper housing 10A. The first porous membrane 31A serves to control the diffusion rate of the gas introduced from the gas inlet 12 of the upper housing 10A and supports the working electrode 32A. The working electrode 32A is formed on the lower surface of the first porous film 31A. The method for forming the working electrode 32A is not particularly limited, and may be formed using, for example, screen printing, compression coating, sputtering, evaporation, or the like. The first porous membrane 31A may be formed to have a slightly smaller diameter than the upper housing 10A, and the working electrode 32A may be formed to have a smaller diameter than the first porous membrane 31A. For example, the first porous membrane 31A may be formed to have a diameter of about 16.8 mm, and the working electrode 32A may be formed to have a diameter of about 10 to 13 mm.

In the working electrode 32A, the ammonia gas in the gas introduced through the gas inlet 12 is oxidized to decompose ammonia to generate hydrogen ions (H ⁺ ). To this end, the working electrode 32A includes a catalyst for the oxidation reaction of ammonia. The catalyst for the oxidation reaction of ammonia contained in the working electrode 32A may be a metal nanoparticle catalyst, preferably ruthenium (Ru) nanoparticles. In this case, the metal nanoparticles may have an average diameter of about 1 to about 10 nm, and preferably about 3 to about 5 nm. The oxidation reaction at the working electrode 32A can be expressed as in the following equation (3).

2NH ₃ → N ₂ + 5H ⁺ + 6e ^- formula (3)

The second porous membrane 31B and the reference electrode 32B are sequentially disposed below the working electrode 32A. The second porous membrane 31B supports the reference electrode 32B. The reference electrode 32B is formed on the lower surface of the second porous film 31B. The method for forming the reference electrode 32B is not particularly limited, and may be formed using, for example, screen printing, compression coating, sputtering, evaporation, or the like. The second porous membrane 31B and the reference electrode 32B are formed to have a smaller size than the working electrode 32A. For example, the second porous membrane 31B and the reference electrode 32B are formed to have a diameter of about 7 mm. Can be. The reference electrode 32B does not participate in direct oxidation and reduction reactions, and maintains a constant potential to calculate the amount of electrical signals generated by the oxidation and reduction reactions of the working electrode 32A and the corresponding electrode 32C. Is the reference point. The reference electrode 32B may be formed to include metal nanoparticles similar to the working electrode 32A so as to maintain a potential similar to that of the working electrode 32A. The metal nanoparticles included in the reference electrode 32B are, for example, gold (Au), carbon (C), cobalt (Co), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), ruthenium (Ru) or the like can be used, and preferably platinum (Pt) can be used. In this case, the metal nanoparticles may have an average diameter of about 1 to about 10 nm, and preferably about 3 to about 5 nm.

The third porous film 31C and the corresponding electrode 32C are sequentially disposed below the reference electrode 32B. The third porous film 31C supports the corresponding electrode 32C. The corresponding electrode 32C is formed on the lower surface of the third porous film 31C. The method for forming the counter electrode 32C is not particularly limited, and may be formed using, for example, screen printing, compression coating, sputtering, evaporation, or the like. In the central portion of the third porous membrane 31C and the corresponding electrode 32C, a through hole 34 penetrating through the third porous membrane 31C and the corresponding electrode 32C is formed, and the third porous membrane 31C is formed. And the corresponding electrode 32C are formed in a donut shape. The ionic liquid electrolyte supported on the electrolyte carrier 40 disposed below through the through hole 34 is transferred to the membrane structures 33A, 33B, and 33C. The third porous film 31C may be formed to have an outer diameter of about 16.8 mm, and the corresponding electrode 32C may be formed to have an outer diameter of about 12 mm, which is smaller than the third porous film 31C. The diameter of the through hole 34 may be about 7 mm.

A reduction reaction occurs at the counter electrode 32C, and water (H ₂ O) is generated from hydrogen ions (H ⁺ ) through the reduction reaction. The counter electrode 32C may be formed to include metal nanoparticles similar to the reference electrode 32B. The metal nanoparticles included in the corresponding electrode 32C are, for example, gold (Au), carbon (C), cobalt (Co), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), ruthenium (Ru) or the like can be used, and preferably platinum (Pt) can be used. In this case, the metal nanoparticles may have an average diameter of about 1 to about 10 nm, and preferably about 3 to about 5 nm. The oxidation reaction at the corresponding electrode 32C can be expressed as in the following equation (4).

_{^{O 2 + 4H + + 4e -}} → 2H 2 O Formula (4)

In the electrochemical ammonia gas sensor 100 according to the present invention, a current flows between the working electrode 32A and the corresponding electrode 32C by an oxidation and reduction reaction generated at the working electrode 32A and the corresponding electrode 32C. From this, the concentration of ammonia gas can be measured.

The membrane structure 33A, 33B, 33C is an ionic liquid which supplies hydrogen ions to at least one of an oxidation reaction occurring at the working electrode 32A and a reduction reaction occurring at the corresponding electrode 32C to have high ion conductivity. The electrolyte is supported and is composed of a first separator 33A, a second separator 33B, and a third separator 33C. The first separator 33A is disposed between the working electrode 32A and the reference electrode 32B and supports the ionic liquid electrolyte, and the second separator 33B is between the reference electrode 32B and the corresponding electrode 32C. The third separator 33C is disposed below the corresponding electrode 32C, and supports the ionic liquid electrolyte. The membrane structures 33A, 33B, and 33C may be made of a material such as glass fiber having acid resistance, alkali resistance, and chemical resistance, and may have a diameter of about 16.8 mm and a thickness of about 0.2 mm.

The electrolyte carrier 40 is disposed below the third separator 33C, and the excess ionic liquid electrolyte is supported so that the ionic liquid electrolyte is supplied to the separator structures 33A, 33B, and 33C. The electrolyte carrier 40 may be made of glass fiber material, the diameter of 16.8 mm, the thickness may be formed of a size of about 7 mm. As described above, the ionic liquid electrolyte supplies hydrogen ions required for the oxidation reaction occurring at the working electrode 32A and the reduction reaction occurring at the corresponding electrode 32C to have high ionic conductivity. Since the ionic liquid electrolyte has low vapor pressure and does not easily evaporate even in a high temperature or low humidity environment, the ionic liquid electrolyte has a long sensor life compared to an acid and alkali electrolyte sensor.

Ionic liquid electrolytes include 1-butyl-1-methylpyrrolinium bis (trifluoromethylsulfonyl) imide, 1-buthyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, 1-Ethyl-3-methylmidazolium Acetate, 1-Ethyl-3-methylimidazolium bis (trifluoromethylsulfornyl imide, 1-Ethyl-3-methylimidazolium dicyanamide, 1-Ethyl-3-methylmidazolium methanesulfonate, 1-Ethyl-3-methylimidazolium tetrafluoromethanesulfonate, 1-Methyllimidazolium chloride, 1-Methylimidazolium hydrogen sulfate, propylene carbonate, Methyl-trioctylammonium bis (trifluoromethyl ) imide and Triethylsulfonium bis (trifluoromethylsulfonyl) imide may include one or more, preferably 1-Ethyl-3-methylmidazolium Acetate.

For stability of the ionic liquid electrolyte, the ionic liquid electrolyte may include at least one additive selected from KCl, LiBr, LiCl, and NaCl, and preferably, may include LiBr additive. And the additive may be contained in the range of 2 to 5% by weight in the ionic liquid electrolyte.

As such, the electrochemical ammonia gas sensor 100 according to the present invention minimizes the interference of the interference gas as compared to the conventional acid and alkali electrochemical ammonia gas sensor. Interference with respect to the interference gas of the electrochemical ammonia gas sensor 100 according to the present invention is shown in Figs.

2 is a view showing a current output value of the electrochemical ammonia gas sensor according to the present invention reacts to six gases (NH ₃ , H ₂ S, H ₂ , NO, CO, CO ₂ ) including ammonia gas, FIG. 3 is an electrochemical ammonia gas sensor according to the present invention shows the output ratio (%) of the ammonia gas output value for the six types of gas (NH ₃ , H ₂ S, H ₂ , NO, CO, CO ₂ ) including ammonia gas The figure shown.

In the case of the conventional acid and alkali electrochemical ammonia gas sensors, for example, the interference with hydrogen sulfide gas shows an output of about 100 to 300% compared to the ammonia gas, as shown in FIGS. 2 and 3, according to the present invention. It can be seen that the chemical ammonia gas sensor 100 exhibits very low hydrogen sulfide interference characteristics of less than 5% of interference with hydrogen sulfide gas, and also shows very low interference characteristics with respect to other gases other than hydrogen sulfide.

In addition, the electrochemical ammonia gas sensor according to the present invention, since the oxidation and reduction reaction occurs directly in the electrode, the reaction time is significantly shortened compared to the conventional acid, alkali electrochemical ammonia gas sensor that oxidation and reduction reaction in the electrolyte. . The reaction time of the electrochemical ammonia gas sensor according to the present invention is shown in FIG. 4. In Figure 4, the reaction time (T ₉₀ ) means the time required until the output ratio reaches 90%.

While the reaction time (T ₉₀ ) of the conventional acid and alkali electrochemical ammonia gas sensor exhibits characteristics of about 90 to 120 seconds, as shown in FIG. 4, the electrochemical ammonia gas sensor 100 according to the embodiment of the present invention. It can be seen that the reaction time of (T ₉₀ ) shows very fast reaction characteristics within 20 seconds.

The electrochemical ammonia gas sensor 100 according to the present invention meets the conditions suitable for the oxidation potential energy of the ammonia gas through the appropriate mixing of the catalyst and the ionic liquid electrolyte for the ammonia oxidation reaction included in the working electrode 32A. It is effective in facilitating the oxidation and reduction of the reaction and maintaining a stable sensor signal. Accordingly, the electrochemical ammonia gas sensor 100 according to the present invention can minimize the interference caused by an interference gas such as hydrogen sulfide (H ₂ S) gas and nitrogen monoxide (NO) gas.

In addition, the electrochemical ammonia gas sensor 100 according to the present invention is not a method of measuring the pH of the electrolyte by changing the ammonia gas is dissolved in the conventional electrolyte, so that the oxidation of the ammonia gas to occur in the electrode immediately In this case, the reaction time of the sensor is shortened, and the electrochemical ammonia gas sensor 100 according to the present invention uses an ionic liquid electrolyte, thereby minimizing the evaporation of the electrolyte in the sensor due to the low vapor pressure characteristic of the ionic liquid electrolyte. It has the effect of increasing the life.

Although the embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described specific embodiments, and the present invention is not limited to the specific scope of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

10A, 10B: housing
11: dust filter
12: gas inlet
20A, 20B, 20C: sensor pin
21A, 21B, 21C: Current Collector
31A, 31B, 31C: porous membrane
32A: working electrode
32B: reference electrode
32C: corresponding electrode
33A, 33B, 33C: Membrane
40: electrolyte carrier

Claims (7)

A housing having a gas inlet through which an external gas flows in an upper portion thereof, and a receiving portion formed below the gas inlet;
The housing is disposed below the gas inlet, and includes a catalyst for the oxidation reaction of ammonia. The ammonia gas in the gas introduced through the gas inlet is oxidized to decompose ammonia to generate hydrogen ions (H ⁺ ). Sensing Electrode (Sensing Electrode);
A reference electrode disposed below the working electrode in the housing;
A counter electrode disposed below the reference electrode in the housing and generating water from hydrogen ions through a reduction reaction;
A first separator supporting an ionic liquid electrolyte for supplying hydrogen ions to at least one of an oxidation reaction occurring at the working electrode and a reduction reaction occurring at the corresponding electrode, wherein the first separator is disposed between the working electrode and the reference electrode; A separator structure including a second separator disposed between a reference electrode and the counter electrode and a third separator disposed below the counter electrode; And
And an electrolyte carrier disposed under the third separator in the housing and supporting an excess of the ionic liquid electrolyte so that the ionic liquid electrolyte is supplied to the separator structure.
In order to shorten the reaction time of the sensor, the catalyst included in the working electrode comprises ruthenium (Ru) nanoparticles, the ionic liquid electrolyte is characterized in that it comprises 1-Ethyl-3-methylimidazolium Acetate Electrochemical ammonia gas sensor. delete The method of claim 1,
Electrochemical ammonia gas sensor, characterized in that the diameter of the ruthenium nanoparticles is 1 to 10 nm. delete delete The method of claim 1,
The ionic liquid electrolyte further comprises one or more additives selected from KCl, LiBr, LiCl and NaCl electrochemical ammonia gas sensor. The method of claim 6,
The additive is an electrochemical ammonia gas sensor, characterized in that contained in 2 to 5% by weight in the ionic liquid electrolyte.

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